After rewriting World War II with Inglorious Basterds, Quentin Tarantino returns to revisionist history with Django Unchained. Loosely tackling the issue of slavery in America via a blood-soaked and often hilarious revenge story, Tarantino's eighth feature-film is his most controversial yet.

Littering his trademark dialogue with N-bombs and showing numerous scenes of brutal violence, Tarantino has left the PC crowd up in arms. It's easy to see how covering such an atrocious part of American history in such a free-wheeling film could be perceived as irresponsible, but who says tackling big issues can only be done in a stodgy, historically-accurate period piece? The film may be strewn with the kind of stylized violence Tarantino is known for but when it comes to the real atrocities of slavery, he clearly shows there's nothing funny about a man being torn apart by dogs or a woman being left naked in a box to bake in the hot sun.

Through the film's co-lead, Tarantino also gives an outsider's perspective as dapper German dentist/bounty hunter Dr. King Schultz (Christoph Waltz) finds Django (Jamie Foxx) in a chain gang and purchases him, promising him freedom in exchange for help finding three white slave-owners.

Along the way, Schultz learns that Django and his wife (Kerry Washington) – whose German owners named her Broomhilda and taught her German - were sold off separately to keep them apart. Schultz is moved by Django's story and vows to help him find his beloved Broomhilda, leading the pair on a journey across the South, encountering numerous colourful characters and wreaking bloody revenge on Django's former owners along the way.

They eventually track down Broomhilda to Candieland, a plantation owned by Calvin Candie (Leonardo DiCaprio), a vile Francophile who can't speak any French. Schultz talks his way into Candieland on the pretence that he is looking to buy a 'mandingo', a slave trained to fight other slaves to the death while their owners bet on the outcome. Django is presented as Schultz' assistant and an expert in mandingo fighting, allowed all of the courtesies of a white man, much to the chagrin of Candie's head house-slave Stephen (Samuel L. Jackson).

These are some of the most memorable characters Tarantino has created. Waltz plays Schultz as a more benevolent variation of his Oscar-winning turn as Hans Landa in Basterds, his unique cadence perfectly suited to the rhythm of Tarantino's dialogue.

The real standouts here however are DiCaprio and Jackson, both playing characters we've never seen from them before. DiCaprio breaks away from his stern leading man persona to play a smooth-talking Southern gent with an overly polite exterior. Jackson gives his best performance in years – perhaps since Tarantino's Jackie Brown – as the most repulsive character in recent memory, a gruesome 'Uncle Tom' who plays the obsequious servant in public but proves a shrewd advisor to Candie behind closed doors. It's an astonishing performance that is as funny as it is menacing.

In the titular role, Jamie Foxx is almost lost amongst these larger than life characters but it's Django who has the main arc in the film and Foxx gives the film a solid centre to allow the madness to go on around him.

As with all of Tarantino's films to date, the film is directed with so much style and verve that every scene feels vibrant and lively, even scenes of just two people talking. The film flows effortlessly from one scene to another, each one luxuriously playing out in its own time while flitting between scenes of broad comedy and frantic violence. There are also scenes of immense tension with a dinner scene at Candieland echoing the incredible bar scene from Basterds.

While Tarantino masterfully orchestrates so many stunning scenes, there's a lack of discipline here that mars the film's last half-hour. It reaches a natural conclusion that would have been just as satisfying and left a tighter film. Instead the film goes off on a meandering journey that only leads back to the same place, killing the momentum of the last act. Sadly the self-indulgence doesn't stop there are Tarantino also crams in his own cameo, complete with a terrible Australian accent.

It's that rambling last act that keeps the film from being truly vintage Tarantino, up there with Basterds and Pulp Fiction. But 'lesser Tarantino' is still fantastic and Django Unchained is a wild genre mashup packed with classic scenes and memorable characters, creating a conversation about slavery without having to preach to the audience.